The present invention relates in general to control assemblies. In particular, the present invention relates to an interface control switch.
The combination of an off/on switch, or set of contacts used to energize and de-energize an electronic circuit from a power source is known. A potentiometer including a three terminal resistor with an adjustable center connection that can change the output resistance by moving the center tap from one end of the potentiometer to the other has been used as a control device. Both of the previous controls are activated by the rotation of a shaft. This type of control is used for power and volume control in radio and television receivers.
Another type of switch/control used in appliances, such as electric ranges is the infinite switch or electromechanical energy regulator. This type of switch/control has internal contacts used to energize and de-energize an electrical circuit, or to perform the off/on power control to a heating element. This type of switch also performs another function by incorporating a bimetal strip connected to the contacts that energize and de-energize the heater. When the bimetal strip is heated, one side of the strip expands faster than the other side. This action opens the contacts stopping the current flow to the heater. As the strip cools the bimetal strip returns to its original position and the contacts close which re-energizes the heater. The bimetal strip can be heated by the use of a small heater in close proximity to the strip or by passing current through the bimetal strip and heating it internally. The amount of time the switch is closed or open can be adjusted by varying the amount of pressure used to restrict the movement of the bimetal strip.
One embodiment of the present invention provides a switch assembly, including a shaft, a first switch and a second switch, a potentiometer including a first and a second terminal, and an electric controller. The first switch is coupled to a first device, whereas the second switch is coupled to a second device. The shaft is coupled to the first switch and the second switch, and is moved to a first position to selectively connect power, through the first switch, to the first device, and to a second position to selectively connect power, through the second switch, to the second device. The potentiometer is coupled to the shaft, and provides a variable resistance between the first and the second terminal in relation to the movement of the shaft. The electric controller is coupled to the potentiometer, and electrically controls the power to the first device and/or the second device in relation to the variable resistance between the first and the second terminal of the potentiometer.